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Owning a swimming pool is not always fun, and pool owners can testify to that. For pool maintenance, you need a variety of products and equipment to ensure that your pool is safe, clean, warm, and perfect for usage.
One of these many products is a pool shock. Many would definitely be wondering what pool shocks are, and simply put; pool shocks are products used to rid your pool of bacteria and algae as well as to clarify and clean your pool water.
As we are sure, you would ask what’s the best pool shock to use; we have here at your disposal a quick yet informative piece that will give you the necessary details on the best pool shock recommendations in the year 2021.
Why Use Pool Shock?
For many pool owners who are used to filters and chemicals, the idea of a pool shock seems like something they already do as part of regular maintenance, but the truth is pool shocking is a little bit more than some chlorine in the pool.
First off, a pool shock is a method whereby a high dosage of chlorine level is delivered to the pool with the sole aim of clearing and purifying your pool of harmful bacteria and pool algae as well as clarifying the swimming pool water to prevent cloudy water.
The pool shocks are used to sanitize the pool water, save you from having to swim in cloudy water, and boost the free chlorine levels in the pool water. Take note that free chlorine is actually considered good chlorine that is designed to kill bacteria and algae.
Top 3 Recommendations
- Best Overall – HTH 52028 Ultimate Shock Treatment
- Runner Up – SpaGuard Enhanced Spa Shock
- Best Pool Shock Treatment – Clorox Pool&Spa 33506CLX Pool Shock Xtra Blue
The Best Pool Shock Reviews
1. HTH 52028 Ultimate Shock Treatment – Best Super Shock Treatment
Pool owners that want to give their swimming pools a full-blown power shock to keep their pools clean and healthy, then HTH Ultimate Shock Treatment is the perfect choice for you.
The fast-dissolving formula of HTH offers you crystal clear water within 24 hours of use, ridding your pool of bacteria and algae alongside other contaminants. A reason why it’s one of the best pool shock products.
It contains built-in clarifiers with about 52.5% of calcium hypochlorite, which makes it perfect for green water treatment. Once added to the pool water, it turns blue to show it’s working; it can be added directly to the pool and softens the water.
The composition prevents scale formation, and it’s compatible with any pool liner as well as for above-ground pools and inground pools as well as a saltwater pool. HTH chlorine shock composition reduces skin and eye irritation. One bag treats 13,500 gallons at once effectively.
- Prevents scale formation
- Features blue coloring to show shock action
- Softens and cleans water
- Compatible with all pool types including saltwater pools
- Only available in 1-pound packs of 6 or 36
2. SpaGuard Enhanced Spa Shock – Best Spa and Hot Tub Treatment
Need the perfect shock for your spa or hot tub, then SpaGuard Enhanced spa shock fits.
The SpaGuard shock is a multi-functional swimming pool shock that not only shocks your pool but also clarifies and serves as a flocculent and pH buffer.
Unlike other pool shock options, SpaGuard shock restores your spa water’s sparkling clean looks and removes any unpleasant odor within 15 minutes of treatment.
It’s compatible with chlorinated or brominated spas and also spas using ozone or ionization systems.
- Offers 4 in 1 functions
- Fast-acting for tub and spa
- Safe for both bromine and chlorine spas and hot tubs
- Sanitizes and removes unpleasant smell
- Not ideal for pools
3. Clorox Pool&Spa 33506CLX Shock Xtra Blue – Best for Vinyl Pools
For vinyl swimming pools that have a more delicate make and are within a smaller range, the Clorox Pool Spa Shock is the right product.
Asides from clearing cloudy water Clorox assures you a pool free from the toughest contaminants within 15 minutes of application. Considered as one of the best pool shocks, it is a perfect choice for black algae, green algae, and of course, for pool algae composition of all forms.
Clorox improves swimming pool filtration and does not affect the pool’s pH, reducing chlorine odor and eye irritation.
- Perfect for vinyl liners and pools
- Tough antibacterial action
- Contains cyanic acid to stabilize the free chlorine
- Perfect for small pools and delicate pools
- Lower chlorine concentration makes it less effective
4. Rx Clear Super Shock for Swimming Pools – Best Calcium Hypochlorite Shock
Rx Clear Super Shock is the perfect shock with the perfect amount of calcium hypochlorite with healthy chlorine levels that contains up to 68% of the calcium hypochlorite and 65% available chlorine.
As a super shock product fitting for all pool types, it serves as a sanitizer, clarifier, and algicide offering you a cleaner and clear blue water treatment.
It is a great choice for regular treatment; it measures 1 pound per 10,000 gallons and works best at night. It’s also guaranteed to raise the pH level of the swimming pool.
- High chlorine levels
- Multi-functional shock
- Perfect for algae treatment
- Raises the pH level of the pool
- Functions best at night as its unstabilized chlorine
5. Austin’s Pool Tech 000176 Pool Tech Shock – Best Liquid Pool Shock
Austin’s Pool Tech pool shock offers you chlorine shock in liquid chlorine format with an assurance of high-level functionality.
A perfect quick action of 1 pound per 10,000 gallons and double for 20,000 gallons, it is an easy-to-use liquid chlorine shock.
The composition is great, with chlorine composition including 12.5% of Sodium hypochlorite. Austin’s Pool Tech pool shock works well to clear the pool water without creating a scale buildup and without changing the cyanic acid levels in the water.
- Quick and effective
- Easy measurement usage
- No scale buildup
- Does not change the acidic levels in the water
- Weak chlorine levels that render it almost ineffective
- Expensive compared to the quality offered
6. Nava Chemicals StarPlus 1-1301-12 Chlorinating Shock Treatment – Best Sodium Dichlor Shock
Perfect for an inground pool and above ground pool, this is one of those swimming pools that require a little less chlorine Nava Chemicals StarPlus is one of the best pool shocks to consider in that category.
Containing about 55.5 % of Sodium Dichlor in its chlorine levels, it’s a quick-dissolving shock that guarantees no scale build-up and is a perfect use for pools as well as spas.
Dosage per-use is easy with one pound per 10,000 gallons, and it’s a stabilized pool shock that will get the job done.
- Sodium dichlor based pool shock
- Suitable for all pool types
- Quick dissolving
- No scale build-up
- A little expensive compared to other products
7. Zappit 73% Cal Hypo Pool Shock – Best Powder Treatment
As the best powder treatment, Zappit Pool Shock is not just the best powder treatment but also one of the best calcium hypochlorite shocks on the market.
With up to 73% of Calcium Hypochlorite in its composition, it is a strong shock option to tackle severe and moderate contaminations. The product is also a great choice for hard water cleaning.
For dosage, a 50-pound bucket can treat up to 16,500 gallons of water, and it does not require premixing. Good for destroying algae, bacteria and cleaning out waste.
- Tough action for severe and moderate contamination
- High calcium Hypochlorite composition
- Good pool cleaning capacity
- Not good for delicate liners
8. In The Swim Chlorine Pool Shock – Best Quick Action Treatment
For a pool owner with a dire dirty pool situation or who owns a saltwater pool that requires regular maintenance, In The Swim Chlorine shock makes a perfect choice.
In The Swim offers pre-portioned powerful chlorine shock treatments that clear out cloudy waters, eliminate algae, bacteria, and other contaminants and provide quick action whenever needed.
With a 68% Calcium Hypochlorite present, it is a powerful, quick action for extremely dirty water or salt water pools and also great for Intex pool cleaning.
- Great for salt water pools
- Kills algae and bacteria
- A powerful pool sanitizer
- Great value
- Can damage vinyl pools
When to apply pool shock?
The best time to apply pool shock to your swimming pool is in the evening when there is little to no sunlight and when there is no swimming.
This is so because the sun’s rays affect the effectiveness of the chlorine, thereby dissolving it quickly before it can act on the pool, and also because the added chlorine could be irritating to skin and eyes.
As for frequency, pool shocks should occur weekly to ensure healthy swimming pool water that is free from cloudy water, dirt, and other organic contaminants. But cases like large pool uses, heavy rainfall, and frequent pool usage require you to shock the pool more often.
How much pool shock should I use?
There is no specific quantity as pool sizes differ per pool owner, but as a general rule, you should dissolve 1 pound per 10,000 gallons of pool water, and this one pound could be of either sodium dichlor or sodium hypochlorite or calcium hypochlorite.
This means 1 pound per 10,000 gallons of water. Also, do not forget to consult the instructions on the pool shock products.
Can pool shock be used as chlorine?
No! Pool shocks cannot be used as chlorine.
The reason being that pool shocks comprise more intense chemicals with a higher chemical strength compared to the average pool chlorine concentration; hence it shouldn’t be used in place of chlorine.
Will pool shock kill mosquito larvae?
Unfortunately, pool shock can kill mosquito larvae but in a moderate amount.
To rid the pool completely of mosquito larvae, you would need a large dosage of chlorine which is both unhealthy to pool users and quite expensive in the long run without appropriate guarantee. Other products you can use to rid the pool of mosquito larvae are mosquito dunks and methoprene granules.
Will pool shock lower pH?
No! Pool shocks do not lower the pH level in the pool; rather, the shock raises it.
Since a major component of the chlorine shock is calcium hypochlorite, which contains a high pH, it is expected that when added to the pool water, the pool pH will rise.
Buying Guide: Tips for Choosing the Best Pool Shock
The amount of chlorine present in a pool shock is what we refer to as the level of chlorine, and to know which type of pool shock is best, you need to know the kind with the best chlorine level to use.
Calcium hypochlorite pool shock is the most used and common form of pool shock treatment. The chlorine level is often between 50-80% and is a quick, potent pool water treatment. When it comes in contact with the sun it can lead to.
Sodium hypochlorite pool shock is found in liquid pool shock treatments with a concentrated formula of 12.5% that allows for large pool treatment with up to 20,000 gallons of water.
Sodium dichloro-s-triazinetrione pool shock comes with a lower chlorine level than the calcium hypochlorite with about 40-50%. This type, however, adds cyanuric acid to the pool water, thereby affecting the overall pH balance of the pool.
Potassium monopersulfate is considered a chlorine-free pool or a non-chlorine shock best for salt water pools as they help remove chloramines. The chlorine-free shock system only works with pools with existing chlorination systems and is great for users who wish to swim chlorine-free.
Pool shock forms
Powder pool shock
These are loose powdery forms of the varying chlorine composition in a pouch or bucket and are measured for effective use. The pool treatment can be added directly to the pool or premixed to avoid damaging the liner, especially vinyl liners.
Liquid pool shock
As the liquid chlorine version of the pool shock treatment contains sodium hypochlorite solution, the liquid pool shock dissolves and disperses faster as it’s already mixed. It’s less expensive compared to the powdery form and must be handled with care as they are highly potent.
Tablet pool shock
As the slowest of all forms as it takes approximately 1-2 hours for the tablets to completely dissolve in water before functioning. But despite the slow dissolve rate, it is pretty effective.
Stabilized or unstabilized
The chlorine pool shock comes in a variety of stabilized pool shocks or unstabilized chlorine pool shocks.
The stabilized pool shock is the one that contains sodium dichlor, which includes a lower chlorine level and can withstand the UV ray damage, and often has an added cyanuric acid, which makes it stable.
The unstabilized pool shock contains the normal chlorine chemical without any additives or stabilizers like cyanuric acid. Hence, it cannot withstand the sun’s rays and break down with sunlight.
While stabilized pool shocks are best for outdoor pools, indoor pools would do better with unstabilized pool shock.
The ideal pH level of any pool ranges from a pH of 7 to 7.8. A pH level above 7.8 has the water too alkaline, and this can cause red, swollen eyes and eye irritation. While one below 7 will have the water being too acidic, which can damage the skin.
Adding a pool shock changes the pH level of the pool; this means that you need a pool shock that will not terribly offset your pool pH level and that would, at the same time, be effective at killing bacteria and keeping your pool clean.
When buying pool shock, the dissolving time of the shock treatment matters, and the faster the swimming pool shock dissolves, the quicker it works, of course, but pool shock treatment forms have different dissolving speeds.
The liquid pool shock products have the fastest dissolving time as they are already in liquid form. The slower ones are the powder pool shock products that dissolve within minutes of application, while the tablet pool shocks take the longest time with a dissolving time frame of about 1-2 hours.
As pool shocks contain some harsh substances which, when they mix with other pool chemicals, can damage the pool floor and liner, you often need to know the best to use.
For vinyl pools or saltwater pools, it’s best to use nonchlorine shock or chlorine-free pool shock products, as the chlorine-based ones can bleach the vinyl liner.
While fiberglass pools and concrete pools have some resistance when considering undissolved shock, you can use a pool shock product like the Cal Hypo pool shock or Pool Essentials Shock Treatment to treat them.
As part of the regular maintenance of your pool, a pool shock treatment is always advisable. Asides from killing bacteria and algae, the best pool shock treatments help clarify your swimming pool water making it safe for usage at all times.
Whether your pool would be needing a super shock treatment or a regular shock treatment, knowing the best pool shock to use for your swimming pool will help you care for your pool better.